Targeted drug delivery across the blood-brain barrier is an extremely challenging quest in the fight with fatal brain ailments, with the major hurdles being short circulation time, reticuloendothelial system (RES) uptake, and excretion of nanocarriers. PEGylation has emerged as a boon for targeted drug delivery to the brain. It is well established that PEGylation can increase the circulation time of nanocarriers by avoiding RES uptake, which is indispensable for increasing the brain's uptake of nanocarriers. PEGylation also acts as a linker for ligand molecules to achieve active targeting to the brain. Using PEGylation, novel approaches are being investigated to facilitate ligand-receptor interactions at the brain endothelium to ease the entry of therapeutic drugs into the brain. In addition, PEGylation made it simpler to assess the brain tissue for delivering diagnostic molecules and theranostic nanocarriers. The potential of PEGylated nanocarriers is being investigated vastly to boost the therapeutic effect several fold in the treatment of brain diseases. This review sheds light on the contribution of PEGylated nanocarriers, especially liposomes, polymeric nanoparticles, and dendrimers for brain-specific delivery of bioactives.

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聚乙二醇化纳米载体：将其靶向递送至大脑的有前途的工具。

在致命性脑疾病的斗争中，跨血脑屏障的靶向药物递送是一项极富挑战性的追求，主要障碍是循环时间短，网状内皮系统（RES）摄取和纳米载体排泄。聚乙二醇化已成为靶向药物向大脑输送的福音。众所周知，聚乙二醇化可以避免RES的摄取，从而延长纳米载体的循环时间，这对于增加大脑对纳米载体的摄取是必不可少的。聚乙二醇化还充当配体分子的连接子，以实现对大脑的主动靶向。使用聚乙二醇化，正在研究新颖的方法以促进脑内皮上的配体-受体相互作用，从而简化治疗药物进入大脑的过程。此外，聚乙二醇化使评估大脑组织中输送诊断分子和诊断学纳米载体的过程变得更加简单。大量研究了聚乙二醇化纳米载体的潜力，以提高脑部疾病治疗的几倍疗效。这项审查阐明聚乙二醇化的纳米载体，尤其是脂质体，聚合物纳米颗粒和树状聚合物对脑特异性生物活性物质的贡献。